Qualcomm QPNP PMIC Temperature Alarm

QPNP temperature alarm peripherals are found inside of Qualcomm PMIC chips
that utilize the Qualcomm SPMI implementation. These peripherals provide an
interrupt signal and status register to identify high PMIC die temperature.

Required properties:
- compatible:      Should contain "qcom,spmi-temp-alarm".
- reg:             Specifies the SPMI address and length of the controller's
                   registers.
- interrupts:      PMIC temperature alarm interrupt.
- #thermal-sensor-cells: Should be 0. See thermal.txt for a description.

Optional properties:
- io-channels:     Should contain IIO channel specifier for the ADC channel,
                   which report chip die temperature.
- io-channel-names: Should contain "thermal".
- qcom,temperature-threshold-set: Defines the temperature threshold set to
		   configure.  Supported values are 0 to 3.  Each set defines
		   the over-temperature stage 1, 2, and 3 temperature
		   thresholds. If this property is not specified, then set 0
		   will be used by default.
		   Threshold set mapping (TEMP_GEN1, TEMP_GEN2 rev 0):
			0 = {105 C, 125 C, 145 C}
			1 = {110 C, 130 C, 150 C}
			2 = {115 C, 135 C, 155 C}
			3 = {120 C, 140 C, 160 C}
		   Threshold set mapping (TEMP_GEN2 rev 1 and above):
			0 = { 90 C, 110 C, 140 C}
			1 = { 95 C, 115 C, 145 C}
			2 = {100 C, 120 C, 150 C}
			3 = {105 C, 125 C, 155 C}

Example:

	pm8941_temp: thermal-alarm@2400 {
		compatible = "qcom,spmi-temp-alarm";
		reg = <0x2400 0x100>;
		interrupts = <0 0x24 0 IRQ_TYPE_EDGE_RISING>;
		#thermal-sensor-cells = <0>;

		io-channels = <&pm8941_vadc VADC_DIE_TEMP>;
		io-channel-names = "thermal";
	};

	thermal-zones {
		pm8941 {
			polling-delay-passive = <250>;
			polling-delay = <1000>;

			thermal-sensors = <&pm8941_temp>;

			trips {
				passive {
					temperature = <1050000>;
					hysteresis = <2000>;
					type = "passive";
				};
				alert {
					temperature = <125000>;
					hysteresis = <2000>;
					type = "hot";
				};
				crit {
					temperature = <145000>;
					hysteresis = <2000>;
					type = "critical";
				};
			};
		};
	};

